Preparation method of atomic-scale uniform array antenna salient points

Abstract

The invention belongs to the technical field of composite material preparation, and particularly relates to a preparation method of atomic-scale uniform array antenna salient points, which adopts a chemical deposition method and comprises the following steps: firstly, depositing on a monocrystalline silicon wafer substrate to obtain an ultra-flat copper film; preparing a mixed system of a copper-containing complexing solution and a reducing solution, flatly laying the mixed system on the surface of the ultra-flat copper film, introducing ammonia gas for reaction, and forming a nano-array bump structure on the surface of the copper film through in-situ growth; and after cleaning, drying in the shade and heating post-treatment, the planar copper foil with the nano array salient point structure is prepared. The method disclosed by the invention is simple in process and strong in controllability, the surface of the obtained copper foil is provided with uniformly distributed nano array salient point structures, the specific surface area and the surface activity of the copper foil are remarkably improved, and the copper foil has wide application prospects in the fields of radars, 6G antennas, electronic devices, heat dissipation materials, catalyst carriers and the like.

Description

Technical Field

[0001] This invention belongs to the fields of transmitting and receiving devices, nanoarray materials, and optoelectronic detection and communication technologies, and specifically relates to a method for preparing atomically uniform array antenna bumps. Background Technology

[0002] As core components in communication, detection, and sensing, transmitting and receiving devices directly determine the signal transmission efficiency, detection accuracy, energy consumption, and application scenario adaptability of the entire system. They are widely used in key areas such as wireless communication, radar detection, quantum sensing, and spaceborne equipment. With the rapid iteration of modern electronic devices towards miniaturization, flexibility, high integration, and high precision, and the surge in demand for multi-form application scenarios (such as curved and spherical devices), the inherent technological bottlenecks of existing transmitting and receiving devices are becoming increasingly prominent, severely restricting technological upgrades and industrial development in related fields. Specifically, these bottlenecks manifest in the following aspects: First, at the core performance level, existing transmitting and receiving devices cannot achieve precise nucleation and uniform arrangement of atomic-level metal clusters, resulting in low emission point density and limited signal-energy superposition efficiency, making it difficult to meet the demands of high-frequency, high-precision communication and detection. Atomic-scale uniform arrangement is crucial for improving signal transmission stability and enhancing energy utilization. Traditional fabrication processes, limited by insufficient precision, cannot achieve this core requirement, becoming the primary bottleneck restricting device performance improvement. Secondly, in terms of form factor adaptation and large-scale application, existing devices struggle to fabricate flexible, large-area, and film-mountable array structures, exhibiting poor adaptability in area and form, and failing to meet the installation requirements of various carrier shapes, including planar, curved, and spherical surfaces. Particularly for spherical curved antennas, traditional fabrication processes suffer from difficulties in forming, uneven curvature, and easy deformation, making it difficult to guarantee ultra-high precision roundness and failing to meet the application requirements of spherical devices. Furthermore, regarding fabrication processes and device stability, existing fabrication processes are prone to phenomena such as metal cluster stacking and protrusions, resulting in poor device surface flatness, affecting parallel light output and detection accuracy, and failing to meet the requirements of scenarios with high output and reception accuracy. Addressing these numerous bottlenecks in existing transmitting and receiving devices, the industry currently lacks an effective solution that can simultaneously achieve atomically uniform arrangement, flexible large-area fabrication, multi-form adaptability, prevention of metal cluster stacking, natural parallel light output, ultra-high roundness of spherical curved surfaces, and also meet the needs of industrial mass production.

[0003] The purpose of this invention is to overcome the shortcomings of existing technologies and provide an array transmit and receive antenna with atomic-level precision, ultra-high density, flexible and bendable surface, large area mass production capability, and low power parallel light output. It also provides a complete, stable, and industrially feasible fabrication method, while ensuring planar flatness from the substrate source. This solves the industry problems of insufficient array growth precision and poor roundness of curved surface formation, and has important practical significance and industrial value for promoting technological progress in the fields of communication, detection, and sensing. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art. This invention provides a method for fabricating atomically uniform array antenna bumps.

[0005] A method for fabricating atomically uniform array antenna bumps, employing a chemical deposition method, includes the following specific steps: Step S1: Select a single-crystal silicon wafer with a diameter of 30cm and a flatness Ra≤0.1nm as the substrate. After cleaning, obtain a clean and flat silicon substrate and place it horizontally at the bottom of a container. Mix 0.005-0.02mol / L copper chloride solution and 0.05-0.1mol / L hydrazine hydrate solution evenly, adjust the pH to ≤5 with hydrochloric acid, pour into a container and let stand for 5-10 minutes. Slowly introduce ammonia gas to deposit an ultra-flat copper foil on the surface of the silicon substrate. Peel the copper foil off from the silicon substrate without damage to obtain an ultra-flat copper foil. Step S2: Preparation of Solution A: Take 40 ml of 0.1 mol / L tetraethylenepentamine solution and 10 ml of 0.1 mol / L butyraldehyde solution, mix and react completely, add 40 ml of 0.1 mol / L copper chloride solution, stir to complex, and let stand. Take 4.2 ml of copper complex solution and add it dropwise to 995.8 ml of PEG-200 solution with pH=4 and concentration of 1%, stir evenly, and prepare Solution A with a copper ion concentration of 0.00042 mol / L. Preparation of solution B: Prepare 990 ml of a solution containing 2% hydrazine hydrate, adjust the pH to 4 with hydrochloric acid, and 1% PEG-200. Let the solution stand for later use. Preparation of solution C: Take 10 ml of solution A and add it dropwise to 990 ml of solution B while stirring. Stir until fully mixed to obtain solution C. Let it stand for later use. Step S3: Take 7 ml of the mixed solution C obtained in Step S2 and spread it evenly on the surface of the horizontally placed ultra-flat copper foil with a diameter of 30 cm obtained in Step S1. Let it stand and soak, and measure the average thickness of the liquid film as 0.1 mm. Slowly introduce ammonia gas and let it stand to react and generate 4 copper group clusters, which sink into the surface of the copper foil. After cleaning and air drying, a nano-array bump structure of 4 copper groups with high density, good uniformity, neat arrangement, and consistent height, with equal spacing and 4 nanometer intervals, is formed on the ultra-flat copper foil base. Heat to 150℃-350℃ to make the bumps bond tightly with the copper foil, and obtain a planar copper foil with a nano-array bump structure. The planar copper foil array with nanoarray bump structure has a tip spacing of 3-5 nm and an array density of 5.10-6.25 × 10⁻⁶. 16 pcs / m 2 .

[0006] Furthermore, the planar copper foil with the nano-array bump structure is shaped using a copper foil forming device, including a horn-shaped cavity. The lower end of the horn-shaped cavity is connected to a gas source through an air pipe. The gas source is a low-temperature high-pressure gas source with a temperature of 30°C and a pressure of 0.6 MPa. The upper end of the horn-shaped cavity is connected to the lower connecting ring. A heating band is also installed on the outer wall of the upper end of the horn-shaped cavity. Thermally conductive silicone is coated on the upper surface of the lower connecting ring. The horn-shaped cavity is filled with high-temperature resistant lightweight sponge. It also includes a spherical forming mold, in which copper foil is formed. The mold cavity of the spherical forming mold faces the horn-shaped cavity, and the surface is uniformly distributed with micropores of 1μm to 2μm for venting. An upper connecting ring that mates with a lower connecting ring is installed at the lower end of the spherical forming mold. The upper end of the spherical forming mold is connected to a hydraulic cylinder via a guide post. The hydraulic cylinder drives the spherical forming mold to rise and fall via the guide post, thereby forming a mating mechanism with the horn-shaped cavity. Further, the shaping process includes the following steps: Step 1: Install the copper foil forming device and connect it to the low-temperature, high-pressure gas source; Step 2: Apply thermally conductive silicone to both the lower and upper connecting rings; Step 3: Place the copper foil at the top of the horn-shaped cavity, with the edge of the copper foil extending beyond the lower connecting ring; Step 4: Start the hydraulic cylinder, which drives the forming spherical mold to descend via the guide column. The upper connecting ring and the lower connecting ring cooperate to press the edge of the copper foil and form a seal. Step 5: Turn on the heating belt, control the temperature at 150℃, maintain for 1 minute, and then turn it off to heat the edge of the copper foil first. Step 6: Control the low-temperature high-pressure airflow into the trumpet-shaped cavity through the throttle valve, and increase the pressure to 0.6 MPa within 1-6 minutes to deform the copper foil and fit it into the spherical mold cavity. During this period, exhaust is carried out through micropores and maintained for 5-10 minutes to allow the copper foil to fully solidify. Step 7: Depressurize through the air pipe, and the copper foil is shaped; Step 8: Start the hydraulic cylinder and drive the forming spherical mold to rise and fall through the guide column. The formed copper foil will detach from the forming spherical mold under its own weight and remain at the top of the trumpet-shaped cavity. Remove and store for later use.

[0007] Beneficial effects: When tetraethylenepentamine and succinaldehyde are mixed in deionized water, a Schiff base reaction occurs. Upon addition of copper chloride and PEG-200, multiple nitrogen atoms on the tetraethylenepentamine chain donate lone pairs of electrons, reacting with Cu... 2+ Coordinate bonds are formed, and the resulting four-arm bridging structure fixes copper ions in specific positions, resulting in uniform spacing between the copper atom clusters after reduction and preventing aggregation. The slow introduction of ammonia acts as an alkaline activator, raising the local pH value. The alkaline condition is necessary for the reduction of Cu by hydrazine hydrate. 2+Ammonia is not only a base but also a good ligand. During reduction, ammonia molecules can weakly coordinate with copper atoms or intermediate-valence copper ions on the surface. When ammonia is slowly introduced, the concentration of ammonia molecules adsorbed on the copper atom surface is moderate, neither excessively hindering growth nor depriving surface atoms of sufficient mobility. Atoms spontaneously move from higher-energy unstable positions to lower-energy lattice positions, eliminating minute defects. The slow introduction of ammonia avoids the formation of large particles caused by localized overconcentration, ensuring the uniformity of atomic clusters across the entire substrate. Attached image description: Figure 1 This is a schematic diagram of a copper foil forming device.

[0008] The components include: 1. Connecting column; 2. Connecting pipe; 3. Horn-shaped cavity; 4. Insulation layer; 5. Heating belt; 6. Lower connecting ring; 7. Thermally conductive silicone; 8. Copper foil; 9. Upper connecting ring; 10. Molding spherical mold; 11. Micropores; 12. Guide column; 13. Sponge. Detailed Implementation

[0009] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0010] Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention. Experimental methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions or as recommended by the manufacturer. Unless otherwise stated, all percentages, ratios, proportions, or parts are by weight.

[0011] Unless otherwise specified, the reagents and raw materials used in the embodiments and comparative examples of this invention are commercially available.

[0012] Example 1 A method for fabricating bumps in an atomically uniform array antenna includes the following steps: Step S1: Select a 30cm diameter monocrystalline silicon wafer as the substrate. The surface flatness of the monocrystalline silicon wafer should not exceed 0.2nm. Clean the wafer using a standard RCA cleaning process to remove surface organic matter, impurities, and oxide layers, obtaining a clean and flat monocrystalline silicon surface. Dissolve copper chloride in deionized water, and mix a 0.01mol / L copper chloride solution with a 0.08mol / L hydrazine hydrate solution to obtain a mixed solution. Uniformly coat the mixed solution onto the surface of the above-treated monocrystalline silicon wafer, and introduce ammonia gas to allow copper chloride and hydrazine hydrate to undergo an in-situ reduction reaction on the silicon surface, generating elemental copper which is deposited on the silicon substrate surface. Control the reaction time and temperature to maintain the copper film thickness at 0.3-0.5mm, obtaining an ultra-flat copper foil with the same flatness as the silicon substrate. The copper-plated wafer obtained above is subjected to rapid temperature change treatment, and then subjected to gentle thermal expansion and contraction treatment with 40°C warm water to remove the metal film from the silicon template without damage, thereby obtaining an independent, ultra-flat copper film with a surface flatness of ≤0.2nm without damage.

[0013] Step S2: Preparation of Solution A: Mix 40 ml of 0.1 mol / L tetraethylenepentamine solution with 10 ml of 0.1 mol / L butyraldehyde solution until the reaction is complete. Add 40 ml of 0.1 mol / L copper chloride solution, stir to form a complex, and let stand. Take the copper complex solution and add it dropwise to 995.8 ml of 1% PEG-200 solution (pH=4), stir well, and prepare Solution A with a copper ion concentration of 0.00042 mol / L. Gold, silver, and other ions can be prepared using the same method. Preparation of Solution B: Prepare 990 ml of solution containing 2% hydrazine hydrate, adjust the pH to 4 with hydrochloric acid, and add PEG... Prepare solution B by taking 200 mL of a 1% solution and letting it stand for later use. To prepare solution C: Take 10 mL of solution A and add it dropwise to 990 mL of solution B while stirring continuously until fully mixed to obtain solution C. Let it stand for later use.

[0014] Step S3: Take 7 ml of the mixed solution C obtained in Step S2 and spread it evenly on the surface of the horizontally placed ultra-flat copper foil with a diameter of 30 cm obtained in Step S1. Let it stand and soak for 15 min, and calculate the average thickness of the liquid film to be 0.1 mm. Slowly introduce ammonia gas at a flow rate of 150 sccm for 3 minutes. After standing and reacting, 4 copper group clusters are generated and sink into the surface of the copper foil. After cleaning and air drying, a nano-array bump structure with high density, good uniformity, neat arrangement, and consistent height of 4 copper groups, equal spacing, and 4 nanometer intervals is formed on the ultra-flat copper foil base. Heat to 200℃ to make the bumps bond tightly with the copper foil, and obtain a planar copper foil with a nano-array bump structure.

[0015] Example 2 The method for fabricating atomic-level uniform array antenna bumps involves using a planar copper foil with a nano-array bump structure obtained in Example 1, and performing the fabrication in a copper foil forming apparatus, such as... Figure 1 As shown, it includes a horn-shaped cavity 3 with a large opening at the top and a small opening at the bottom, made of stainless steel. The horn-shaped cavity is wrapped with an insulation layer 4, which is an insulation coating. The lower end of the horn-shaped cavity is fixed to a fixing frame (not shown in the figure) by a connecting column 1. The lower end of the horn-shaped cavity is connected to a gas source through a gas pipe 2. The gas source is a low-temperature high-pressure gas source with a temperature of 30°C and a pressure of 0.6 MPa. Nitrogen is used for both the low-temperature high-pressure gas source and the gas source.

[0016] The upper end of the horn-shaped cavity is connected to the lower connecting ring 6. A heating belt 5 is also installed on the outer wall of the upper end of the horn-shaped cavity. The horn-shaped cavity located at the heating belt is not covered with a heat insulation layer. Thermally conductive silicone 7 is coated on the upper surface of the lower connecting ring. The horn-shaped cavity is filled with high-temperature resistant lightweight sponge 13, which can disperse pressure and avoid airflow concentration during pressurization. A filter is connected inside the air pipe to prevent the sponge from being discharged with the airflow.

[0017] It also includes a spherical mold 10, in which copper foil 8 is formed. The mold cavity of the spherical mold faces the horn-shaped cavity. The spherical mold is made of stainless steel and has micropores 11 of 1μm to 2μm evenly distributed on its surface for venting. An upper connecting ring 9 that mates with the lower connecting ring is installed at the lower end of the spherical mold. The upper end of the spherical mold is connected to a hydraulic cylinder (not shown in the figure) through a guide post 12. The hydraulic cylinder drives the spherical mold to rise and fall through the guide post, thereby forming a mating with the horn-shaped cavity.

[0018] The forming of spherical copper foil includes the following steps: Step 1: After installing the copper foil forming device, connect the low-temperature high-pressure gas source; Step 2: Apply thermally conductive silicone to both the lower and upper connecting rings; Step 3: Place the copper foil at the top of the horn-shaped cavity, with the edge of the copper foil extending beyond the lower connecting ring; Step 4: Start the hydraulic cylinder, which drives the forming spherical mold to descend via the guide column. The upper connecting ring and the lower connecting ring cooperate to press the edge of the copper foil and form a seal. Step 5: Turn on the heating belt, control the temperature at 150℃, maintain for 1 minute and then turn it off, so that the edge of the copper foil is heated first; Step 6: Control the low-temperature high-pressure airflow into the trumpet-shaped cavity through the throttle valve, and increase the pressure to 0.6 MPa within 3 minutes to deform the copper foil and fit it into the spherical mold cavity. During this period, exhaust is carried out through the micropores and maintained for 5 minutes to allow the copper foil to fully solidify. Step 7: Depressurize through the air pipe, and the copper foil is shaped; Step 8: Start the hydraulic cylinder and drive the forming spherical mold to rise and fall through the guide column. The formed copper foil will detach from the forming spherical mold under its own weight and remain at the top of the trumpet-shaped cavity. Remove and store for later use.

[0019] It can produce copper foil with an outer diameter of 30cm and above, and cut the copper foil to the required area during use.

[0020] By selecting the radius of the spherical mold and the orientation of the planar copper foil array of the nanoarray bump structure, concave or convex spherical structures can be fabricated to meet application requirements.

[0021] Comparative Example 1: 1. Base preparation Ultra-flat copper foil is used as the substrate with a surface roughness Ra≤0.2nm. It is cleaned with deionized water and dried for later use.

[0022] 2. Plating process The conventional chemical copper plating solution of copper chloride and hydrazine hydrate was prepared in the same manner as in Example 1, but without the addition of ammonia, succinaldehyde, tetraethylenepentamine, or PEG-200.

[0023] The coating, reaction, cleaning, and drying processes are carried out according to industry-standard procedures.

[0024] 3. Sample characteristics Visual inspection and surface roughness testing revealed that the conventional copper plating layer had a high surface roughness and insufficient uniformity, with some areas exhibiting obvious particle protrusions, uneven edges, and large undulations, which are typical surface defects of conventional chemical copper plating in the disclosed technology.

[0025] Comparative Example 2: 1. Base preparation Same as in Example 1, but using ultra-flat copper foil.

[0026] 2. Solution preparation The formulations of solutions A, B, and C from Example 1 were used exactly, including the concentration of copper chloride, the content of PEG, the pH value, and the proportions of each component, all of which were consistent with those in Example 1.

[0027] 3. Coating vs. Reaction (Key Difference) Take 7 ml of C solution and spread it evenly on the surface of the ultra-smooth copper foil. The liquid film thickness is 0.1 mm. Let it stand and soak for 15 minutes.

[0028] Key steps: Do not introduce ammonia gas, simply let it stand in the air for the same amount of time, then clean, air dry, and heat to 200°C to cure.

[0029] 4. Sample characteristics Due to the lack of ammonia to induce and trigger the reaction, the system reaction is significantly slow or difficult to start effectively.

[0030] The final surface only forms a thin, discontinuous, and poorly covered deposit, with some areas of the substrate exposed, failing to achieve the uniform and dense effect of Example 1.

[0031] Comparative Example 3: 1. Base preparation Same as in Example 1, but using ultra-flat copper foil.

[0032] 2. Solution Adjustment (Key Difference) Keep the raw materials and formulations such as copper chloride, hydrazine hydrate, and PEG the same as in Example 1, only adjust the molar ratio of succinaldehyde to tetraethylenepentamine: - Example ratio: 1:4 (optimal value) - Control ratio: adjusted to 1:2 3. Coating and Reaction Prepare solutions A and C with corresponding ratios, take 7 ml of each and spread them evenly on the surface of copper foil, with a liquid film thickness of 0.1 mm, and let them stand and soak for 15 minutes.

[0033] Introduce ammonia gas at 150 sccm for 3 minutes, clean, air dry, and heat to 200℃ to cure.

[0034] 4. Sample characteristics When the succinaldehyde content is reduced to a 1:2 ratio, the stability of the complexation system decreases significantly, and the uniform and stable coordination structure in Example 1 cannot be formed.

[0035] The sample surface showed localized uneven deposition, poor continuity, and disordered distribution, which was significantly worse than the 1:4 ratio effect of Example 1.

[0036] Effect Example The following tests were performed on Examples 1-2 and Comparative Examples 1-3 described above. 1. Array Spacing and Array Density: Field emission scanning electron microscopy was used to locate and image the most regularly arranged area of ​​the array at high magnification. Using the instrument's built-in measuring tools, the center points of N ≥ 20 adjacent tips were randomly selected, and their straight-line distances were measured. A rectangular area of ​​known size was delineated on the clear image, and the number of tips within this area was automatically counted using image analysis software.

[0037] 2. Metal film substrate flatness: Atomic force microscopy was used to perform high-resolution scanning in the 500 nm × 500 nm range to assess atomic-level local flatness. First-order or second-order fitting was performed on the acquired images to eliminate artifacts caused by sample tilt, and the root mean square roughness value was read.

[0038] Table 1 shows the test performance of the atomic-level uniform array antennas prepared in the examples and comparative examples.

[0039] As shown in Table 1, Examples 1-2 all satisfy the requirements of an array spacing of 3-5 nm and an array density of 5.1-6.25 × 10¹. 6The requirement of 1 / m², the spacing and density fluctuate slightly with the concentration of copper chloride and the flow rate of ammonia, and the overall performance meets the technical requirements; Example 2 is a spherical copper foil, and the array structure is basically maintained after forming. The spacing and density are close to those of Example 1, and the flatness is slightly improved; Due to process defects, the growth of copper atoms in Comparative Example 1 is irregular, the size of the bumps varies greatly, and the unevenness is visible to the naked eye; Comparative Example 2 does not introduce ammonia and cannot generate 4 copper clusters; Comparative Example 3 adjusts the molar ratio of butyraldehyde and tetraethylenepentamine to 1:2, but cannot form an effective and regular array.

[0040] The above-mentioned solution of the present invention is applicable to highly conductive metals such as copper, nickel, iron, silver, gold and their alloys, and conventional material replacements are all within the scope of protection of this patent.

[0041] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for fabricating bulges in an atomically uniform array antenna, characterized in that, This method uses chemical deposition, and the specific steps are as follows: Step S1: Select a single-crystal silicon wafer with a diameter of 30cm and a flatness Ra≤0.1nm as the substrate. After cleaning, obtain a clean and flat silicon substrate and place it horizontally at the bottom of a container. Mix 0.005-0.02mol / L copper chloride solution and 0.05-0.1mol / L hydrazine hydrate solution evenly, adjust the pH to ≤5 with hydrochloric acid, pour into a container and let stand for 5-10 minutes. Slowly introduce ammonia gas to deposit an ultra-flat copper foil on the surface of the silicon substrate. Peel the copper foil off from the silicon substrate without damage to obtain an ultra-flat copper foil. Step S2: Preparation of Solution A: Take 40 ml of 0.1 mol / L tetraethylenepentamine solution and 10 ml of 0.1 mol / L butyraldehyde solution, mix and react completely, add 40 ml of 0.1 mol / L copper chloride solution, stir to complex, and let stand. Take 4.2 ml of copper complex solution and add it dropwise to 995.8 ml of PEG-200 solution with pH=4 and concentration of 1%, stir evenly, and prepare Solution A with a copper ion concentration of 0.00042 mol / L. Preparation of solution B: Prepare 990 ml of a solution containing 2% hydrazine hydrate, adjust the pH to 4 with hydrochloric acid, and 1% PEG-200. Let the solution stand for later use. Preparation of solution C: Take 10 ml of solution A and add it dropwise to 990 ml of solution B while stirring. Stir until fully mixed to obtain solution C. Let it stand for later use. Step S3: Take 7 ml of the mixed solution C obtained in Step S2 and spread it evenly on the surface of the horizontally placed ultra-flat copper foil with a diameter of 30 cm obtained in Step S1. Let it stand and soak, and measure the average thickness of the liquid film as 0.1 mm. Slowly introduce ammonia gas and let it stand to react and generate 4 copper group clusters, which sink into the surface of the copper foil. After cleaning and air drying, a nano-array bump structure of 4 copper groups with high density, good uniformity, neat arrangement, and consistent height, with equal spacing and 4 nanometer intervals, is formed on the ultra-flat copper foil base. Heat to 150℃-350℃ to make the bumps bond tightly with the copper foil, and obtain a planar copper foil with a nano-array bump structure. The planar copper foil with a nanoarray bump structure has a bump tip spacing of 3–5 nm and an array density of 5.10–6.25 × 10⁻⁶. 16 pcs / m 2 .

2. A method for fabricating convex points in an atomically uniform array antenna, characterized in that, A planar copper foil with a nano-array bump structure is shaped using a copper foil forming device, including a horn-shaped cavity. The lower end of the horn-shaped cavity is connected to a gas source through an air pipe. The gas source is a low-temperature high-pressure gas source with a temperature of 30°C and a pressure of 0.6 MPa. The upper end of the horn-shaped cavity is connected to the lower connecting ring. A heating band is also installed on the outer wall of the upper end of the horn-shaped cavity. Thermally conductive silicone is coated on the upper surface of the lower connecting ring. The horn-shaped cavity is filled with high-temperature resistant lightweight sponge. It also includes a spherical mold, in which copper foil is formed. The mold cavity of the spherical mold faces the horn-shaped cavity, and the surface is uniformly distributed with micropores of 1μm to 2μm for venting. An upper connecting ring that mates with the lower connecting ring is installed at the lower end of the spherical mold. The upper end of the spherical mold is connected to a hydraulic cylinder through a guide post. The hydraulic cylinder drives the spherical mold to rise and fall through the guide post, thereby forming a mating with the horn-shaped cavity.

3. The method for fabricating atomic-level uniform array antenna bumps according to claim 2, characterized in that, The shaping process includes the following steps: Step 1: Install the copper foil forming device and connect it to the low-temperature, high-pressure gas source; Step 2: Apply thermally conductive silicone to both the lower and upper connecting rings; Step 3: Place the copper foil at the top of the horn-shaped cavity, with the edge of the copper foil extending beyond the lower connecting ring; Step 4: Start the hydraulic cylinder, which drives the forming spherical mold to descend via the guide column. The upper connecting ring and the lower connecting ring cooperate to press the edge of the copper foil and form a seal. Step 5: Turn on the heating belt, control the temperature at 150℃, maintain for 1 minute, and then turn it off to heat the edge of the copper foil first. Step 6: Control the low-temperature high-pressure airflow into the trumpet-shaped cavity through the throttle valve, and increase the pressure to 0.6 MPa within 1-6 minutes to deform the copper foil and fit it into the spherical mold cavity. During this period, exhaust is carried out through the micropores and maintained for 5 minutes to allow the copper foil to fully solidify. Step 7: Depressurize through the air pipe, and the copper foil is shaped; Step 8: Start the hydraulic cylinder and drive the forming spherical mold to rise and fall through the guide column. The formed copper foil will detach from the forming spherical mold under its own weight and remain at the top of the trumpet-shaped cavity. Remove and store for later use.

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